Effect of Time, Temperature, and Root Exudates on the Development of Rotylenchulus reniformis

時間、溫度、及根部分泌物對腎形線蟲發育之影響

蔡碧雲(Bie-Yun Tsai) ； 黃慧真(Huei-Zhen Huang)

《植物病理學會刊》 20卷3&4期 (2011/12) Pp. 108-117

https://doi.org/10.6649/PPB.201112_20(3_4).0006

摘要

腎形線蟲Rotylenchulus reniformis的年輕雌蟲是侵入寄主的唯一齡期。這個特性對R. reniformis之研究的精確度造成干擾，因為卵孵化後尚需額外的努力才能得到具侵入能力的齡期。用二齡幼蟲接種可能造成有效接種原之量不一致的問題，使得不同實驗之間無法做比較。了解影響R. reniformis發育的因子有助於製備研究所需之有效接種原。本研究包括時間、溫度、及根部分泌物對腎形線蟲發育之影響。年輕雌蟲及雄蟲之百分比隨著時間而增加，於室溫下在水中21天後分別達到26.0%及17.7%。當線蟲一直保存在15°C時僅出現極少數之年輕雌蟲。當線蟲一直保存在28°C時年輕 雌蟲之百分比在25天後達到最高，40.6%。在收集新孵化之線蟲時先保存在15°C一星期然後才以28°C處理者年輕雌蟲之百分比在25天後達到38.9%。雄蟲之數目在15°C之處理最低。在15°C-28°C及28°C之處理雄蟲之百分比隨時間而增加，於25天後分別達到40%及36.8%。綠豆根部分泌物處理者年輕雌蟲及雄蟲之百分比與對照組無顯著差異。在15°C之處理雄蟲之百分比高於年輕雌蟲。在15°C-28°C及28°C之處理於16至25天之間雄雌比率接近1:1。低溫時雄蟲之發育較年輕雌蟲快。本研究之結果有助於製備R. reniformis具侵入能力之齡期，而每個實驗可因而精確指出所使用之有效接種原的量，有利於不同實驗之間的比較。本研究之結果亦對腎形線蟲之基本生物學之瞭解有所貢獻。

關鍵字

發育 ； 根部分泌物 ； 侵入齡期 ； 接種原 ； 腎形線蟲 ； 性別比率 ； 溫度 ； 時間 ； Rotylenchulus

並列摘要

The young female is the only infective stage in the life cycle of Rotylenchulus reniformis. This feature poses interference in the precision of the researches of R. reniformis due to the extra effort required to obtain the effective inoculums, the infective stage of the nematodes, after hatching of the eggs. Using the second-stage juveniles as inoculum source has the potential problem of inconsistent level of effective inoculums and the comparison between different researches cannot be made. Understanding of the factors affecting the development of R. reniformis will help the improvement of the preparation of effective inoculums for researches. The effect of time, temperature, and root exudates on the development of the reniform nematodes was investigated. The percentage of young females and males increased with time after hatching and reached 26.0% and 17.7%, respectively, at 21 days in water at room temperature. There were very few young females developed when the nematodes were kept at 15°C throughout the experiment. The percentage of young females reached the highest, 40.6%, at 25 days when the nematodes were kept at 28°C throughout the experiment. The percentage of young females was 38.9% at 25 days when the nematodes were kept at 15°C for one week while collecting the newly hatched nematodes and then kept at 28°C throughout the experiment. The amount of males was the lowest at 15°C among the temperature treatments. The percentages of males increased with time in the 15°C-28°C and 28°C treatments and reached 40% and 36.8%, respectively, at 25 days. The percentages of young females and males in the root exudates of mung bean were not significantly higher than that in the control. The mean percentages of the males were higher than that of the females in the 15°C treatment. The male to female ratio was close to 1:1 from 16 to 25 days in the 15°C-28°C and 28°C treatments. The males developed faster than the young females at low temperature. The results of our study may help in the preparation of the infective stage of R. reniformis and the amount of effective inoculums used in each experiment can then be pinpointed to facilitate the comparison of researches between different researchers. Besides helping in the improvement of the precision of R. reniformis researches, our study also adds to the understanding of the basic biology of this nematode.

並列關鍵字

development ； exudates ； infective stage ； inoculums ； reniform nematode ； Rotylenchulus ； sex ratio ； temperature ； time